Application of wavefunction-based ab initio methods to extended systems
نویسندگان
چکیده
The quantum-mechanical problems of solving the electronic Hamiltonian of realistic system on an ab initio level is mainly tackled with the density functional approach, which relies on the ground-state density of the system and avoids the calculation of the many-body wavefunction of the system. However, the present DFT-based approaches are not amenable to systematic improvements. Therefore, it is desirable to include correlations within the many-body wavefunction, using so-called quantum-chemical methods for the correlation. Especially for the strongcorrelated systems (like molecular magnets) the explicit determination of the many-body wavefunction is of great importance with respect to proper description of their electronic properties.
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